Built 2026-10-19 (19 October 2026)

Iron River Threshold Days by Year (USC00204093)

17 fixed thresholds counted per year at Iron River (USC00204093): hot days, frost, tropical nights and heavy rain, with the most days in a year.

Key Facts for Iron River Thresholds

  • Iron River: days with 10 mm (0.39 in) or more of precipitation in 24 years, most in 1911 with 57.
  • Iron River: days with 25 mm (0.98 in) or more of precipitation in 24 years, most in 1911 with 16.
  • Iron River: days with a maximum temperature at or above 30 C (86 F) in 20 years, most in 1921 with 48.
  • Iron River: days with a maximum temperature at or below 0 C (32 F) in 20 years, most in 1900 with 107.
  • 17 fixed thresholds have at least one qualifying day at Iron River.
20 years with a qualifying day
Days at or above 30 C (86 F) per year at Iron River Days per year at Iron River with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 48 in 1921. 02040601900: 111903: 31904: 41905: 41906: 161907: 51908: 161909: 141910: 271911: 281912: 161913: 181914: 181915: 51916: 271917: 101918: 81919: 231920: 111921: 481900190419061908191019121914191619181920
Days per year at Iron River with a maximum temperature at or above 30 C (86 F), with the decade average as a line. The most was 48 in 1921.
Days at or above 30 C (86 F) per year at Iron River
YearDaysDecade average
1900119.1
190339.1
190449.1
190549.1
1906169.1
190759.1
1908169.1
1909149.1
19102718
19112818
19121618
19131818
19141818
1915518
19162718
19171018
1918818
19192318
19201129.5
19214829.5
First to last qualifying date each year at Iron River For each year, a bar from the first to the last day at Iron River meeting 30 C (86 F). 1900: 13 May 1900 to 19 August 19001903: 7 July 1903 to 23 July 19031904: 16 July 1904 to 27 July 19041905: 16 July 1905 to 29 August 19051906: 17 May 1906 to 11 September 19061907: 16 June 1907 to 11 August 19071908: 21 June 1908 to 21 September 19081909: 20 June 1909 to 19 September 19091910: 14 June 1910 to 21 August 19101911: 19 May 1911 to 16 August 19111912: 10 June 1912 to 5 September 19121913: 13 June 1913 to 6 September 19131914: 26 May 1914 to 20 September 19141915: 13 July 1915 to 5 September 19151916: 4 July 1916 to 20 August 19161917: 21 July 1917 to 31 July 19171918: 5 May 1918 to 25 August 19181919: 26 May 1919 to 7 September 19191920: 31 May 1920 to 14 September 19201921: 20 May 1921 to 4 September 19211900190519081911191419171920JanFebMarAprMayJunJulAugSepOctNovDec
For each year, a bar from the first to the last day at Iron River meeting 30 C (86 F).
First to last qualifying date each year at Iron River
YearFirst dateLast date
19001900-05-131900-08-19
19031903-07-071903-07-23
19041904-07-161904-07-27
19051905-07-161905-08-29
19061906-05-171906-09-11
19071907-06-161907-08-11
19081908-06-211908-09-21
19091909-06-201909-09-19
19101910-06-141910-08-21
19111911-05-191911-08-16
19121912-06-101912-09-05
19131913-06-131913-09-06
19141914-05-261914-09-20
19151915-07-131915-09-05
19161916-07-041916-08-20
19171917-07-211917-07-31
19181918-05-051918-08-25
19191919-05-261919-09-07
19201920-05-311920-09-14
19211921-05-201921-09-04

Every Fixed Threshold

Fixed thresholds at Iron River
ThresholdYears with a qualifying dayMost days in a yearYearLatest year days
30 C (86 F): Days2048192148
35 C (95 F): Days810192110
90 F (32.2 C): Days1820192120
100 F (37.8 C): Days2119111
0 C (32 F): Ice days (max20107190082
0 C (32 F): Frost days (min192291917181
-10 C (14 F): Days with min19114190872
-20 C (-4 F): Days with min1951191614
-30 C (-22 F): Days with min191919121
-40 C (-40 F): Days with min3219121
20 C (68 F): Tropical nights (min12719217
10 mm (0.39 in): Days with 10 mm or more rain2457191123
25 mm (0.98 in): Days with 25 mm or more rain241619114
50 mm (1.97 in): Days with 50 mm or more rain12319031
100 mm (3.94 in): Days with 100 mm or more rain2119031
10 cm (3.9 in): Days with 10 cm or more snowfall161019111
25 cm (9.8 in): Days with 25 cm or more snowfall3219082

Years with under 90 percent of days observed are left out of the most days column. Threshold history at this station starts in 1900.

Download the Data

  • Data for Iron River threshold days by year: CSV or JSON. Field meanings are on the data page.

Source: NOAA National Centers for Environmental Information, Global Historical Climatology Network Daily (GHCN-Daily). Records are computed by World Extreme Weather Monitor and are not official NOAA products. (US Government open data (NOAA NCEI)) Data as of 2026-10-17 (17 October 2026). Threshold counts are computed by this site.

Data as of . Last revised (2025-12-31).